Dissimilar Welding of Nickel-Based Superalloy - A Review

Fundamental investigation of mechanical properties on different types of dissimilar welded joints was described in this paper. Dissimilar metal welding was generally employed in chemical and petrochemical plants, oil and gas industries, nuclear power plants and aerospace industries etc. For enriching the structural integrity of aerospace industries, material with high temperature resistance and high corrosion resistance is needed. For fulfilling the above criteria, Inconel 718 (IN 718) was selected due to its felicitous strengths such as yield, tensile, and creep at high temperatures with significant corrosion properties. This paper reviews the different welding processes and the impact they have on mechanical properties, as well as some difficulties related to welding dissimilar metals. Gas Tungsten Arc Welding (GTAW) process comprises high micro-hardness and tensile strength properties during dissimilar welding of IN 718. SS 410 and Inconel 625 materials hold high micro-hardness and tensile strength values respectively. The effect of IN 718 filler metal has also been discussed in this paper. Some of the dissimilar welding defects can be eliminated by IN 718 filler metal. This paper will give better directions to the researchers to focus on future studies.